Half the posters automatically assume that snowden is working for the other side and that he's part of a negative propaganda campaign against the US.
How scary is the world you live in? It's like the brains can't process the possibility of something not having an ulterior motive.
So, are you saying it's *possible* that all this wasn't just a setup by Putin? Yea, and it's *possible* for the sun to rise in the west...
If you think Putin would willingly subject himself to questioning by Snowden, when he didn't have a really good idea what he was going to be asked and how he was going to answer, and that Snowden was free to ask any question that crossed his mind, you need to get your tinfoil hat back on...
Even the questions you can ask are provided by the state..
OF COURSE it was scripted and likely highly edited. This is 100% propaganda aimed squarely at the west by Putin. Snowden is just being used to attract attention and shape the message. He's just a pawn in a much larger game.
Reading between the lines though, I wonder what Putin is up to. Why bother with this?
You fell for the "waste heat" argument garbage didn't you... So sorry.
The conversion of heat energy to another form (electricity in this case) requires the TRANSFER of heat from a source to a sink. What we "dump" in the sink is called "waste heat" but that does not imply it is somehow useable to produce more power output from the plant (assuming a modern power plant). The most efficient conditions for an idea heat engine is when the heat is transferred at a constant temperature and in modern power plants they go to great lengths to approach this ideal.
Thermoelectrics generally require fairly high temperature differentials to operate. By the laws of thermodynamics, this means that they are never going to be efficient, and trying to use them in a power plant simply cannot be helpful to it's efficiency. Sorry, the laws of thermodynamics still apply here.
The article never talked about massive gains in heat efficiency for power plants, just scavenging waste heat.
You are falling for the waste heat argument. Power is generated by the transfer of heat from a high temperature source to a low temperature sink. In a power plant, we've managed to engineer them pretty well and we get pretty close to the ideal. Any new device will have to exceed the existing efficiency or it simply will not help, but hurt. Remember it is the TRANSFER of heat that is used to produce power, not the heat energy itself. So the "dumping of waste heat" is not a power loss in the system where you can hope to get gains from.
If you are familiar with the ideal cycle, remember that this cycle requires the transfer of heat to and from the working fluid/gas at a constant temperature. The devices being described require fairly high temperature differentials to operate. They simply *cannot* be as efficient because of this, and if I understand the physics, they will never really be all that more efficient than they are now.
Where I'm dubious about the usefulness of this technology in cars, I would agree that there is at least a possibility it could help. Thermodynamics would allow it. However, in a power plant, Thermodynamics tell me they are not useful.
I also wonder if the original author and the researchers involved actually understand the issues, given they try and present this as a way to improve a power plant. On that point they are totally and obviously mistaken. If they are that far off on that point, I have to start questioning the rest of their ideas because they are obviously either ignorant or deliberately misleading.
The maximum limit on an an arbitrary heat-conversion system is that doesn't break accepted theory is the Carnot-cycle heat engine, where eff 1 - T_cold / T_hot (as measured from absolute 0). But it's a rare real-world engine that gets anywhere near the Carnot efficiency limit - a car engine might run at 1100K for an ideal efficiency of around 73%, but the reality in most cars is closer to 25%. Being solid-state a thermoelectric device could potentially operate at very near the ideal (no mechanical losses), roughly tripling the efficiency. Assuming 90% efficient electric wheel motors the total system efficiency could be nearly as high.
Don't be fooled that "hey they are solid state and convert directly to electricity". Deep down, it's still a physical process that produces electricity, even if the moving parts are not something you can see. In actual practice, what happens with these things produces horrible efficiency.
These electronic devices are semiconductor junctions that you get heat to flow through in hopes the electrons will bounce their way across the junction into the cooler side and get stuck... They are not efficient from a thermodynamic perspective, and unless my physical understanding of how they work is totally wrong, they are never going to approach the efficiency of even an internal combustion engine, from a thermodynamic perspective anyway.
Before you make a bigger ass of yourself, please look up what "waste heat" actually is and familiarize yourself with the "Thermo" in thermodynamics.
Engines run HOT. Every bit of heat that travels into the metal and outside the engine is lost energy. Capturing bits of that lost energy and putting it to good use is the concept here. This is waste heat, so it is free, just as eating food out of the garbage bin is "free food" -- someone else paid for it, but they threw it out so it is "free" for you. It's not disobeying thermodynamics any more than burning a gallon of gasoline to make a car move 30 miles is disobeying the laws of thermodynamics.
For other automotive-related things that defy your idiotic concept of physics, please see turbochargers and hybrid cars.
If you read my post.... (and apparently you didn't)... I specifically stipulate that automotive applications *might* be successful and worth of investigation. The reason I say this is because of the huge amounts of heat transferred out the tail pipe and radiator in a modern internal combustion engine at sometimes very high temperature differentials leaves something to recover. This is totally unlike a modern power plant, where heat transfer has been carefully engineered to be as efficient as possible, thus leaving little room for thermodynamic improvement. However, my doubts about automotive application are over costs, weight and complexity not about the Thermodynamics of the application.
Until these devices they describe approach the current efficiency of a power plant, there is zero chance they will be helpful on an industrial scale. Modern power plants are usually within a few percentage points of ideal so these devices are going to have to come way up the efficiency scale, and they are horrible now. Given how they work at the subatomic level (holes, electrons etc) I seriously doubt we are in any danger of reaching this level.
I'm not sure how the cooling works for PV cells. But, if they are actively cooling the liquid there is little to be gained from this arrangement and it is likely going to lead to hotter cell temperatures and cooler liquid temperatures.
So it *might* work, but only if the temperature differential they can stand is high enough and they are not expending energy to cool the liquid through some heat engine.... (I.e. if they use something like a swamp cooler or something.)
Nuclear power plants are very efficient, yet they still use cooling towers and still run millions of gallons of heated water through cooling ponds. This technology is about capturing waste heat, which is the product of a process which has already obeyed all the rules of thermodynamics.
Here we go "waste heat". Please learn a bit more about thermodynamics and heat engines. Power is generated from the TRANSFER of heat. Power plants are huge heat engines, that produce electrical power by taking heat from a high temperature source, transferring that heat to a low temperature sink. There is very little WASTE in a power plant (nuclear or otherwise). Yes you have to dump heat to generate power, but it is not like you are just wasting power when you dump heat. This "waste heat" is not a free resource you can exploit to get more power from the plant.
Adding any other devices in the path of the heat flow will only impede the heat flow and drive down efficiency. I contend that the loss of efficiency will be more than the power you can generate using devices that directly convert heat transfer to electrical power. These devices are not nearly as efficient as what we have already in a modern power plant, thus there is zero chance they will be better.
It is hard, as before 2000 it was no FUD.
About current day cyber attacks I have no opinion.
Except: would take me 5 minutes to cause a USA wide power outage. Well, worst case 50... in fact every one with google skills likely needs less than 24h to figure how to take it down. I would call that a serious thread and not FUD.
If 50 min is all it takes, then why as it not happened? Surely there is some nut job out there crazy enough to do it and smart enough to pull it off. Surely... It's not like all the folks in the middle east are somehow stupid, and a lot of them have serious issues with the USA and would love nothing more than to put us all in the dark, if even for a short time. Wide spread outages, caused by somebody hacking, simply have not happened. Why? If it is so easy, surely somebody would have tried it by now because there are a lot of smart people out there who would be willing to do it.
I strongly suspect you are making stuff up now.. So this is where we stop.
There's a lot of energy available from an IC engine. If you doubt me let your car run for anything more than two minutes and then touch the exhaust manifold. Bumped one with my arm when I was in high school and it took twelve years for the scar to fade.
Which is why I stipulate that these heat to electricity devices MIGHT be of value for internal combustion engines. The heat dumped by them is significant and the temperature differential quite high. There is at least opportunity to get something that would normally just get dumped. I just openly wonder if for a car or truck it will be worth the cost, weight and complexity it will add. I strongly suspect that it's not worth it, but I'm not totally sure.
Any energy you manage to get, will be lost someplace else because you put these devices in the heat flow.
You sir, are ignorant . It's a sad comment on the state of affairs that a clueless bullshit comment like your could be moderated informative.
We've been extracting energy from waste heat, without incurring extra losses, for over a century now - i
Calm down and think about what I said. Your average power plant is pretty darn good efficiency wise (which is what I said if you don't mind reading), which is exactly what you are saying too. Yea, we've come a long way from just dumping waste steam, we have optimized things very well actually. I'm saying that there is very little room for improvement left at this point and there is NO FREE LUNCH here. These devices that convert heat flow directly to electric power are NOT going to increase the efficiency of industrial scale power plants. These devices are simply NOT EFFICIENT enough and will disrupt the current efficiency we've already designed in, they will only disrupt the heat flow, raise entropy and result in less power output for the same input. They don't help.
Don't let them fool you with all this "waste heat" garbage, at least until you understand the Thermodynamic laws that govern all this and can explain what a heat engine is.
Before cautioning others to educate themselves, first pull your head out of your own ass and educate yourself.
What on earth did I say that was incorrect? I admit to having struggled with thermodynamics class, but I believe I captured the essence of heat engines and efficiency. So you want to step down off the pedestal and discuss exactly what you think I have wrong in my understanding of thermodynamics? Or are you going to stay up there and keep yelling about how stupid everybody else is?
I don't know about you, but I've been talking exclusively about the power grid.. Which was what the original article was about.
If you want expand from there, I've seen Y2K problems as recently as a month ago. Not that it mattered that my sprinkler controller isn't Y2K aware. First of March, just pick a year that starts on the right day of the week and it will work, at lest until the end of February. All you have to do is ignore the year in the mean time.
I never said Y2K wasn't a problem, only that all the yahoos who thought the Apocalypse was upon us as we approached January 1, 2000 and the grid was going to fail and the banks where going down too, where out to lunch. As out to lunch as the crazies who are saying the same thing about cyber warfare taking down the grid now...
Look, these things are NOT going to get you thermodynamic efficiency gains on anything of value. Any system which is designed to be efficient now, will not benefit from this kind of heat to electricity device. Thermodynamic rules demand a maximum efficiency that is as good as you can do. Most industrial scale energy production is pretty darned good compared to the maximum possible. So you are NOT going to be able to just hook up these things and get electrical energy for *free* (even without the device costs). Any energy you manage to get, will be lost someplace else because you put these devices in the heat flow. Don't even bother trying this, it simply won't work. Don't let them fool you with all this "waste heat" garbage, at least until you understand the Thermodynamic laws that govern all this and can explain what a heat engine is.
As I concluded before, in situations where you have less than ideal conditions, like in cars with internal combustion engines, you MIGHT get a little bit of energy, but I ask you is it going to be worth it? Are you sure you are going get enough gain to make it worth the weight, cost and complexity? Where I'm not so sure that answer is a good one, I'm willing to entertain that it *might* be possible for internal combustion engines. Go ahead and work on that idea, but I'm fairly sure it's not going to work very well.
I'd also suggest that there are more efficient heat engines you might consider. These heat flow direct to electricity devices are horribly inefficient compared to the ideal.
A cyber attack has more potential to bring the grid down for an extended time than Y2K did. Y2K would have been random-like failures and would have covered limited areas. A deliberate attack OTOH would be targeted at the grid's weak spots and would be more likely to result in physical damage to critical equipment. It's not the end of the world scenario some would have us believe, but it's a potentially serious problem.
IMHO, the risk of a Y2K issue on January 2nd, 2000 was higher than a successful cyber attack is today.. (Yes, that's a full 24 hours after the 2 digit year rolled over..)
.... I was claiming that the FUD about the Y2K bug taking down the electric grid or doing away with society as we know it was FUD...
Example code aside, how many *real live* issues have you seen from Y2K bugs that didn't get fixed? None worth mentioning? None that caused the loss of life or property. Yea, me too. I got nothing either. Seems the *problem* got fixed for the most part.
Slashdot Mirror
Half the posters automatically assume that snowden is working for the other side and that he's part of a negative propaganda campaign against the US.
How scary is the world you live in? It's like the brains can't process the possibility of something not having an ulterior motive.
So, are you saying it's *possible* that all this wasn't just a setup by Putin? Yea, and it's *possible* for the sun to rise in the west...
If you think Putin would willingly subject himself to questioning by Snowden, when he didn't have a really good idea what he was going to be asked and how he was going to answer, and that Snowden was free to ask any question that crossed his mind, you need to get your tinfoil hat back on...
Even the questions you can ask are provided by the state..
OF COURSE it was scripted and likely highly edited. This is 100% propaganda aimed squarely at the west by Putin. Snowden is just being used to attract attention and shape the message. He's just a pawn in a much larger game.
Reading between the lines though, I wonder what Putin is up to. Why bother with this?
He's a traitor and a corrupt piece of crap. He's caused more harm to world peace than even Putin. The two certainly belong together.
Where I agree he's a traitor... I think you ascribe him way too much power. Snowden is, at this point, just a pawn being used by Putin.
While true, your statement also assumes he had a choice...
Either way, it demonstrates that Snowden is a tool. Just not sure what kind...
I agree, but this is no surprise. Snowden has been a tool of Putin the whole time. Why change now?
These propaganda sessions for Putin are pre-staged so Snowden has allowed himself to be used as a "propaganda tool". C
But that is what Snowden has ALWAYS been for Putin, a propaganda tool. Why should it change now?
You fell for the "waste heat" argument garbage didn't you... So sorry.
The conversion of heat energy to another form (electricity in this case) requires the TRANSFER of heat from a source to a sink. What we "dump" in the sink is called "waste heat" but that does not imply it is somehow useable to produce more power output from the plant (assuming a modern power plant). The most efficient conditions for an idea heat engine is when the heat is transferred at a constant temperature and in modern power plants they go to great lengths to approach this ideal.
Thermoelectrics generally require fairly high temperature differentials to operate. By the laws of thermodynamics, this means that they are never going to be efficient, and trying to use them in a power plant simply cannot be helpful to it's efficiency. Sorry, the laws of thermodynamics still apply here.
nothing to do with heat engines. THERMOELECTRICS.
Which are subject to the laws of Thermodynamics even if you don't think so....
Your claim is like saying because it's solid state, it has nothing to do with electric fields... Totally and completely false.
Claims like this is where perpetual energy scams get started. "Hey, look at this design, Energy for FREE! (Thermodynamics just *don't* apply.)"
The article never talked about massive gains in heat efficiency for power plants, just scavenging waste heat.
You are falling for the waste heat argument. Power is generated by the transfer of heat from a high temperature source to a low temperature sink. In a power plant, we've managed to engineer them pretty well and we get pretty close to the ideal. Any new device will have to exceed the existing efficiency or it simply will not help, but hurt. Remember it is the TRANSFER of heat that is used to produce power, not the heat energy itself. So the "dumping of waste heat" is not a power loss in the system where you can hope to get gains from.
If you are familiar with the ideal cycle, remember that this cycle requires the transfer of heat to and from the working fluid/gas at a constant temperature. The devices being described require fairly high temperature differentials to operate. They simply *cannot* be as efficient because of this, and if I understand the physics, they will never really be all that more efficient than they are now.
The article mentions power plants near the end.
Where I'm dubious about the usefulness of this technology in cars, I would agree that there is at least a possibility it could help. Thermodynamics would allow it. However, in a power plant, Thermodynamics tell me they are not useful.
I also wonder if the original author and the researchers involved actually understand the issues, given they try and present this as a way to improve a power plant. On that point they are totally and obviously mistaken. If they are that far off on that point, I have to start questioning the rest of their ideas because they are obviously either ignorant or deliberately misleading.
The maximum limit on an an arbitrary heat-conversion system is that doesn't break accepted theory is the Carnot-cycle heat engine, where eff 1 - T_cold / T_hot (as measured from absolute 0). But it's a rare real-world engine that gets anywhere near the Carnot efficiency limit - a car engine might run at 1100K for an ideal efficiency of around 73%, but the reality in most cars is closer to 25%. Being solid-state a thermoelectric device could potentially operate at very near the ideal (no mechanical losses), roughly tripling the efficiency. Assuming 90% efficient electric wheel motors the total system efficiency could be nearly as high.
Don't be fooled that "hey they are solid state and convert directly to electricity". Deep down, it's still a physical process that produces electricity, even if the moving parts are not something you can see. In actual practice, what happens with these things produces horrible efficiency.
These electronic devices are semiconductor junctions that you get heat to flow through in hopes the electrons will bounce their way across the junction into the cooler side and get stuck... They are not efficient from a thermodynamic perspective, and unless my physical understanding of how they work is totally wrong, they are never going to approach the efficiency of even an internal combustion engine, from a thermodynamic perspective anyway.
Before you make a bigger ass of yourself, please look up what "waste heat" actually is and familiarize yourself with the "Thermo" in thermodynamics.
Engines run HOT. Every bit of heat that travels into the metal and outside the engine is lost energy. Capturing bits of that lost energy and putting it to good use is the concept here. This is waste heat, so it is free, just as eating food out of the garbage bin is "free food" -- someone else paid for it, but they threw it out so it is "free" for you. It's not disobeying thermodynamics any more than burning a gallon of gasoline to make a car move 30 miles is disobeying the laws of thermodynamics.
For other automotive-related things that defy your idiotic concept of physics, please see turbochargers and hybrid cars.
If you read my post.... (and apparently you didn't) ... I specifically stipulate that automotive applications *might* be successful and worth of investigation. The reason I say this is because of the huge amounts of heat transferred out the tail pipe and radiator in a modern internal combustion engine at sometimes very high temperature differentials leaves something to recover. This is totally unlike a modern power plant, where heat transfer has been carefully engineered to be as efficient as possible, thus leaving little room for thermodynamic improvement. However, my doubts about automotive application are over costs, weight and complexity not about the Thermodynamics of the application.
Until these devices they describe approach the current efficiency of a power plant, there is zero chance they will be helpful on an industrial scale. Modern power plants are usually within a few percentage points of ideal so these devices are going to have to come way up the efficiency scale, and they are horrible now. Given how they work at the subatomic level (holes, electrons etc) I seriously doubt we are in any danger of reaching this level.
I'm not sure how the cooling works for PV cells. But, if they are actively cooling the liquid there is little to be gained from this arrangement and it is likely going to lead to hotter cell temperatures and cooler liquid temperatures.
So it *might* work, but only if the temperature differential they can stand is high enough and they are not expending energy to cool the liquid through some heat engine.... (I.e. if they use something like a swamp cooler or something.)
Nuclear power plants are very efficient, yet they still use cooling towers and still run millions of gallons of heated water through cooling ponds. This technology is about capturing waste heat, which is the product of a process which has already obeyed all the rules of thermodynamics.
Here we go "waste heat". Please learn a bit more about thermodynamics and heat engines. Power is generated from the TRANSFER of heat. Power plants are huge heat engines, that produce electrical power by taking heat from a high temperature source, transferring that heat to a low temperature sink. There is very little WASTE in a power plant (nuclear or otherwise). Yes you have to dump heat to generate power, but it is not like you are just wasting power when you dump heat. This "waste heat" is not a free resource you can exploit to get more power from the plant.
Adding any other devices in the path of the heat flow will only impede the heat flow and drive down efficiency. I contend that the loss of efficiency will be more than the power you can generate using devices that directly convert heat transfer to electrical power. These devices are not nearly as efficient as what we have already in a modern power plant, thus there is zero chance they will be better.
It is hard, as before 2000 it was no FUD. About current day cyber attacks I have no opinion. Except: would take me 5 minutes to cause a USA wide power outage. Well, worst case 50 ... in fact every one with google skills likely needs less than 24h to figure how to take it down. I would call that a serious thread and not FUD.
If 50 min is all it takes, then why as it not happened? Surely there is some nut job out there crazy enough to do it and smart enough to pull it off. Surely... It's not like all the folks in the middle east are somehow stupid, and a lot of them have serious issues with the USA and would love nothing more than to put us all in the dark, if even for a short time. Wide spread outages, caused by somebody hacking, simply have not happened. Why? If it is so easy, surely somebody would have tried it by now because there are a lot of smart people out there who would be willing to do it.
I strongly suspect you are making stuff up now.. So this is where we stop.
If it lets me kill the phone if the wanker in front of me driving at 20mph, I'll be happy.
Unless the guy behind you has one too and thinks it's your fault..
There's a lot of energy available from an IC engine. If you doubt me let your car run for anything more than two minutes and then touch the exhaust manifold. Bumped one with my arm when I was in high school and it took twelve years for the scar to fade.
Which is why I stipulate that these heat to electricity devices MIGHT be of value for internal combustion engines. The heat dumped by them is significant and the temperature differential quite high. There is at least opportunity to get something that would normally just get dumped. I just openly wonder if for a car or truck it will be worth the cost, weight and complexity it will add. I strongly suspect that it's not worth it, but I'm not totally sure.
You sir, are ignorant . It's a sad comment on the state of affairs that a clueless bullshit comment like your could be moderated informative.
We've been extracting energy from waste heat, without incurring extra losses, for over a century now - i
Calm down and think about what I said. Your average power plant is pretty darn good efficiency wise (which is what I said if you don't mind reading), which is exactly what you are saying too. Yea, we've come a long way from just dumping waste steam, we have optimized things very well actually. I'm saying that there is very little room for improvement left at this point and there is NO FREE LUNCH here. These devices that convert heat flow directly to electric power are NOT going to increase the efficiency of industrial scale power plants. These devices are simply NOT EFFICIENT enough and will disrupt the current efficiency we've already designed in, they will only disrupt the heat flow, raise entropy and result in less power output for the same input. They don't help.
Before cautioning others to educate themselves, first pull your head out of your own ass and educate yourself.
What on earth did I say that was incorrect? I admit to having struggled with thermodynamics class, but I believe I captured the essence of heat engines and efficiency. So you want to step down off the pedestal and discuss exactly what you think I have wrong in my understanding of thermodynamics? Or are you going to stay up there and keep yelling about how stupid everybody else is?
Lisa, in this house, we obey the LAWS OF THERMODYNAMICS!!!!
LOL Why yes, yes we do. Like it or not.
I don't know about you, but I've been talking exclusively about the power grid.. Which was what the original article was about.
If you want expand from there, I've seen Y2K problems as recently as a month ago. Not that it mattered that my sprinkler controller isn't Y2K aware. First of March, just pick a year that starts on the right day of the week and it will work, at lest until the end of February. All you have to do is ignore the year in the mean time.
I never said Y2K wasn't a problem, only that all the yahoos who thought the Apocalypse was upon us as we approached January 1, 2000 and the grid was going to fail and the banks where going down too, where out to lunch. As out to lunch as the crazies who are saying the same thing about cyber warfare taking down the grid now...
I debunked this LAST time it was posted..
Look, these things are NOT going to get you thermodynamic efficiency gains on anything of value. Any system which is designed to be efficient now, will not benefit from this kind of heat to electricity device. Thermodynamic rules demand a maximum efficiency that is as good as you can do. Most industrial scale energy production is pretty darned good compared to the maximum possible. So you are NOT going to be able to just hook up these things and get electrical energy for *free* (even without the device costs). Any energy you manage to get, will be lost someplace else because you put these devices in the heat flow. Don't even bother trying this, it simply won't work. Don't let them fool you with all this "waste heat" garbage, at least until you understand the Thermodynamic laws that govern all this and can explain what a heat engine is.
As I concluded before, in situations where you have less than ideal conditions, like in cars with internal combustion engines, you MIGHT get a little bit of energy, but I ask you is it going to be worth it? Are you sure you are going get enough gain to make it worth the weight, cost and complexity? Where I'm not so sure that answer is a good one, I'm willing to entertain that it *might* be possible for internal combustion engines. Go ahead and work on that idea, but I'm fairly sure it's not going to work very well.
I'd also suggest that there are more efficient heat engines you might consider. These heat flow direct to electricity devices are horribly inefficient compared to the ideal.
My lights stayed on pretty much the whole year before and the year after... But I suppose...
Really?
I'm comparing the historical FUD that came BEFORE January 1 2000, with what I'm calling FUD about cyber attacks today. Come on it's not that hard..
Yes, that's why I said not entirely FUD.
A cyber attack has more potential to bring the grid down for an extended time than Y2K did. Y2K would have been random-like failures and would have covered limited areas. A deliberate attack OTOH would be targeted at the grid's weak spots and would be more likely to result in physical damage to critical equipment. It's not the end of the world scenario some would have us believe, but it's a potentially serious problem.
IMHO, the risk of a Y2K issue on January 2nd, 2000 was higher than a successful cyber attack is today.. (Yes, that's a full 24 hours after the 2 digit year rolled over..)
Your mileage may vary.
.... I was claiming that the FUD about the Y2K bug taking down the electric grid or doing away with society as we know it was FUD...
Example code aside, how many *real live* issues have you seen from Y2K bugs that didn't get fixed? None worth mentioning? None that caused the loss of life or property. Yea, me too. I got nothing either. Seems the *problem* got fixed for the most part.